Barrier units and articles made therefrom
Barrier units and articles made therefrom, particularly constraining bands of high strength and low weight for containing articles, especially in blast resistant container assemblies, are disclosed. The barrier unit comprises a surface having a regular polygonal perimeter with a plurality of substantially parallel sides, each of which terminates in at least one loop integral with the surface. The surface comprises at least one network of high strength fiber with at least about 50 weight percent of the fiber comprising substantially contianuous lengths of fiber aligned in the hoop direction of the loops. The barrier units have utility as constraining bands for loads of articles like logs, and as doors/closures for access openings to the interior of aircraft blast resistant cargo containers. They are also useful as fences and window protectors.
1. A fence barrier useful to provide protection against threats, said fence barrier comprising a plurality of constraining elements, said constraining elements extending in a generally horizontal direction and being vertically spaced from adjacent constraining elements, said constraining elements comprising at least one fibrous network, the fibers of said fibrous network comprising fibers having a tenacity of at least about 10 g/d and a tensile modulus of at least about 200 g/d, and
a plurality of horizontally spaced securing devices that extend in a generally vertical direction, said securing devices being in communication with said plurality of constraining elements to form said barrier.
2. The barrier of claim 1 wherein said fibers have a tenacity of equal to or greater than about 20 g/d and a tensile modulus equal to or greater than about 500 g/d.
3. The barrier of claim 1 wherein said fibers have a tenacity of equal to or greater than about 30 g/d and a tensile modulus equal to or greater than about 1200 g/d.
4. The barrier of claim 3 wherein at least about 50 weight percent of said fibers comprise substantially continuous lengths of fiber extending along the length of said constraining elements.
5. The barrier of claim 4 wherein said fibrous network is in the form of unidirectionally oriented fibers.
6. The barrier of claim 5 wherein said fibrous networks comprise a resin matrix for said unidirectionally oriented fibers.
7. The barrier of claim 6 wherein said fibrous networks comprise a plurality of fibrous sheets that are cross plied.
8. The barrier of clam 1 wherein said fibers comprise fibers selected from the group consisting of extended chain polyolefin fibers, aramid fibers, polybenzoxazole fibers, polybenzothiazole fibers, polyvinyl alcohol fibers, polyacrylonitrile fibers, liquid copolyester fibers, polyamide fibers, glass fibers, carbon fibers, and mixtures thereof.
9. The barrier of claim 1 wherein said fibers comprise extended chain polyethylene fibers.
10. The barrier of claim 1 wherein said constraining elements are in the form of bands having a length and a width, said bands being interrupted across the length thereof to form two ends, said ends comprising at least one integral loop, said integral loops being connected to said securing devices.
11. The barrier of claim 10 wherein said securing devices comprise posts, and said loops extend over said posts.
12. The barrier of claim 1 wherein said securing devices comprise posts.
13. The barrier of claim 12 wherein at least two adjacent posts each secures a plurality of said constraining elements.